The present invention relates to an imaging device, an image processing device, an image processing method, a microscope, and the like.
An imaging device that can acquire information about the incident angle of a light ray that enters an optical system (hereinafter referred to as “light field (LF) information”) has been studied and developed in recent years. Such an imaging device is referred to as “plenoptic camera” or “light field (LF) camera”, and can generate a plurality of images that differ in viewpoint (hereinafter referred to as “disparity images”) from the LF information. Note that the term “viewpoint” used herein refers to a point from which the object is viewed (observed).
For example, image data that includes three-dimensional image information about the object can be generated from a plurality of disparity images generated from the LF information. The term “three-dimensional image information” used herein refers to information that includes information in the depth direction in addition to two-dimensional image information that is obtained using a conventional camera, for example. It is also possible to generate an image in which the object that is situated at an arbitrary imaging distance is brought into focus by processing the image data including the three-dimensional image information, and extracting the light rays that entered the optical system in an arbitrary direction to reconstruct a two-dimensional image.
For example, JP-A-2008-219878 discloses technology that performs an image generation process that corresponds to a focus value designated by the user using image data obtained by a plenoptic camera to generate a display image, and displays the generated display image.
The distance to the object in the depth direction (i.e., three-dimensional image information about the object) can be determined (measured) from a plurality of disparity images generated using a plenoptic camera by applying the principle of triangulation. In this case, triangulation is performed using a straight line that connects the viewpoints of two disparity images as a base line.
When the distance to an edge in the depth direction is determined (instead of the distance to a point in the depth direction) by applying triangulation, the measurement accuracy varies depending on the relationship between the direction of the base line and the direction of the edge. Specifically, it becomes more difficult to detect the disparity between the disparity images, and the distance measurement accuracy decreases, as the direction of the base line and the direction of the edge become parallel to each other. On the other hand, it becomes easier to detect the disparity between the disparity images, and the distance measurement accuracy increases, as the direction of the base line and the direction of the edge become orthogonal to each other.
Specifically, it is necessary to increase the angular resolution in the direction of the base line so as to be able to deal with an arbitrary edge (each edge), and generate a larger number of images viewed from different viewpoints in order to increase the distance measurement accuracy.